It depends on the vibe you want to project. I recently gave a talk at a conference. The vibe I wanted to project was friendly, approachable, humorous, and an expert in my field. I chose P74 (37.5 mcg/spray) and P75 (3.75 mcg/spray). P74 projects a best friend vibe, while P75 projects an alpha vibe without the sexual overtones. The results were phenomenal. You can read about it in my journal (post #19).
It also helps if you can mingle with the audience prior to your presentation. This will get them on board with your mones. I haven’t tried it yet, but IShine solo and MX297 solo might be worthwhile. I’ll have to experiment with those in future talks.